
By: Kuro (offline) Sunday, July 27 2014 @ 02:32 AM CDT (Read 1777 times)



Kuro 
Pls see attachment for questions. No answer keys given. Thanks.

Junior
Registered: 12/31/06 Posts: 27





By: jo sarah (offline) Sunday, July 27 2014 @ 08:18 AM CDT



jo sarah 
hi Kuro,
please see attached, and hope it be helpful and explains solutions clearly.
(this is a reload of the file to correct a typo error on my part; many thanks to Kuro for alerting me.)
Cheerio!

Regular Member
Registered: 03/20/12 Posts: 111





By: jo sarah (offline) Sunday, July 27 2014 @ 08:22 AM CDT



jo sarah 
please ignore this

Regular Member
Registered: 03/20/12 Posts: 111





By: jo sarah (offline) Sunday, July 27 2014 @ 08:25 AM CDT



jo sarah 
So sorry, I was trying to load the file and when it was apparently completed, there wasn't anything, so i tried to reload, thus resulting in these multiple replies.
Please refer to the first reply and ignore all these. Thank you.

Regular Member
Registered: 03/20/12 Posts: 111





By: Kuro (offline) Sunday, July 27 2014 @ 11:35 PM CDT



Kuro 
Hi Sarah,
Regarding Q4, isn't the number of arcs1 1/3 instead of 1 2/3?

Junior
Registered: 12/31/06 Posts: 27





By: echeewh (offline) Monday, July 28 2014 @ 01:11 AM CDT



echeewh 
Hey <Kuro>
Yes if you are referring to your Q4 (a). The Perimeter of the Shaded Parts = Circumference of 1 1/3 circle. ( NOT 1 2/3 circle )
Following are my worked solutions (and references) to Q2, 3, 4:
Q2.
<Solution with a different approach using minimal fraction>
**  for alignment purpose
M ** : A **: U
160 : 100
100 ***** : 65
M : A : U
8 : 5 ******  (1)
20 ** : 13 *  (2)
Since number of cards M has is the same in both comparisons (ratios), we use <Repeated ID> method and find the common multiple of 8, 20. (i.e. 40)
M : A : U
(1)x5
40 : 25 ****  (3)
(2)x2
40 ** : * 26  (4)

40 : 25 : 26
Given that U had 1.5 times as many cards as before in the end, we have ...
U = 1.5 × 26u = 39u
39u  26u = 13u
This infers U received 13u of cards from M, A in the ratio of 3 : 1. We now have ...
4p > 13u
1p > (13/4)u
M : A : U
40 : 25 : 26  (5)
<Gave / Received>
(39/4) (13/4) 13  (6)
(5)x4:
M : A : U
<Before>
160 : 100 : 104
(6)x4:
<Gave/Received>
39 * 13 ** 52
<After>
121 : 87 : 156
Given M had 238 more cards than A in the end, we have ...
M  A = 238
121u  87u = 238
34u > 238
1u > 7
M gave U = 39u > 39 × 7 = 273
=====
Q3.
This is a repeated question.
Kindly refer to my worked solution on current page 29 of Forum  Subject: Maths; Author: <achieve_goal>; Last Posted: 26/6/13, 8.51pm
======
Q4.
This is a repeated question.
Kindly refer to my worked solution on current page 50 of Forum  Subject: Question on Area/Perimeter of Circles; Author: <keenlearner>; Last Posted: 21/12/12, 5.16pm
Remarks:
(a) Perimeter of Shaded Part = Circumference of 1 1/3 circle ( not 1 2/3 circle as indicated in Ms Sarah's solution )
========
Do let me know again if there are clarifications.
Cheers,
Edward

Active Member
Registered: 04/21/11 Posts: 627





By: jo sarah (offline) Monday, July 28 2014 @ 01:43 AM CDT



jo sarah 
Yes, Kuro, I made a careless mistake. The perimeter is 1 1/3 circle, not 1 2/3. Many thanks for pointing it out.
Otherwise, the rest of solutions are ok. Don't need answer keys.
Trust you are able to open the file, so don't need another repeat set of solutions. I'll upload a corrected file when I can do on my PC... something seems amiss when I acess from there.

Regular Member
Registered: 03/20/12 Posts: 111



